1. Field of the Invention
The present invention relates to a substrate processing apparatus and a method of manufacturing a semiconductor device.
2. Description of the Prior Art
As one example of a substrate processing apparatus, a semiconductor manufacturing apparatus is known. In particular, as one example of the semiconductor manufacturing apparatus, a vertical diffusion and Chemical Vapor Deposition (CVD) apparatus is known.
The vertical diffusion and CVD apparatus includes: an outer tube; an inner tube installed inside the outer tube to form a process chamber; a heating device (heater) configured to heat the inside of the outer tube, a manifold on which the outer tube and the inner tube are placed and to which an exhaust pipe and a gas introduction pipe are connected to exhaust the process chamber and supply gas into the process chamber, respectively; and a boat configured to hold a plurality of wafers aligned in a vertical direction and to be loaded into the process chamber.
The boat holding the plurality of wafers is loaded into the process chamber through a lower furnace port, and CVD films are deposited on the wafers by supplying a film-forming gas into the process chamber through the gas introduction pipe and simultaneously heating the process chamber by the heating device.
In such a vertical diffusion and CVD apparatus, as disclosed in Patent Document 1, the manifold (furnace port flange) is made of a metal.
Since the plate thickness of the metallic manifold is thin and the heat capacity thereof is low, heat is easily dissipated to the outside of the furnace port.
[Prior Art Document]
[Patent Document]
[Patent Document 1] Japanese Patent Laid-Open No. 2002-334868
However, the CVD apparatus using the metallic manifold has a problem in that the metallic manifold is corroded by attachment of reaction products that are generated by a reaction gas and a cleaning gas.
Moreover, as ICs are miniaturized, metal emission from the metallic manifold used in the CVD apparatus becomes an issue.
Therefore, in order to suppress metal contamination in a substrate to be processed, exposure of metallic parts inside the process chamber is minimized, and the manifold as well as the outer and inner tubes is made of a non-metal component such as quartz. In addition, as earthquake countermeasures, an inner tube collapse suppression member is provided for suppressing the collapse of the inner tube and is fastened by a bolt made of a non-metal component such as quartz. In the apparatus constructed as above, a reaction product (by-product) generated during the processing of the substrate within the inner tube is frequently adhered around the inner tube collapse suppression member. If the inner tube collapse suppression member is forcibly detached in such a state that the reaction product is adhered thereto, a new problem arises which breaks the bolt or the manifold made of the non-metal component such as quartz. If the bolt is broken and thus could not be taken away from the manifold, or the manifold is broken, the expensive manifold must be replaced or remanufactured.